class Settings():
	"""存储《外星人入侵》的所有设置的类"""
	
	def __init__(self):
		"""初始化游戏的静态设置"""
		# 屏幕设置
		self.screen_width = 1200
		self.screen_height = 800
		self.bg_color = (230, 230, 230)
		
		# 飞船设置
		self.ship_limit = 3
		
		# 子弹设置
		self.bullet_width = 300
		self.bullet_height = 15
		self.bullet_color = 60, 60, 60
		self.bullets_allowed = 5

		# 外星人设置
		self.fleet_drop_speed = 10
		
		# 加快游戏速度比率
		self.speedup_scale = 1.5
		self.initialize_dynamic_settings()
		
		# 记分
		self.alien_points = 50
		
		self.time_passed = 0.0

	def initialize_dynamic_settings(self):
		"""初始化速度"""
		self.ship_speed_factor = 1.5
		self.bullet_speed_factor = 3
		self.alien_speed_factor = 1
		
		# direction为1时表示右移，-1表示左移
		self.fleet_direction = 1
		
	def increase_speed(self):
		"""提高速度, 提升等级"""
		self.ship_speed_factor *= self.speedup_scale
		self.bullet_speed_factor *= self.speedup_scale
		self.alien_speed_factor *= self.speedup_scale
